CA2248952A1 - Dual chamber pacing with interchamber delay - Google Patents
Dual chamber pacing with interchamber delay Download PDFInfo
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- CA2248952A1 CA2248952A1 CA002248952A CA2248952A CA2248952A1 CA 2248952 A1 CA2248952 A1 CA 2248952A1 CA 002248952 A CA002248952 A CA 002248952A CA 2248952 A CA2248952 A CA 2248952A CA 2248952 A1 CA2248952 A1 CA 2248952A1
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- chamber
- cardiac signal
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- heart
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N1/00—Electrotherapy; Circuits therefor
- A61N1/18—Applying electric currents by contact electrodes
- A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
- A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
- A61N1/362—Heart stimulators
- A61N1/3627—Heart stimulators for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N1/00—Electrotherapy; Circuits therefor
- A61N1/18—Applying electric currents by contact electrodes
- A61N1/32—Applying electric currents by contact electrodes alternating or intermittent currents
- A61N1/36—Applying electric currents by contact electrodes alternating or intermittent currents for stimulation
- A61N1/362—Heart stimulators
- A61N1/365—Heart stimulators controlled by a physiological parameter, e.g. heart potential
- A61N1/368—Heart stimulators controlled by a physiological parameter, e.g. heart potential comprising more than one electrode co-operating with different heart regions
Abstract
A method and apparatus for determining the origin of a cardiac signal in the heart of a patient. A cardiac stimulator includes a multiple-chamber electrode arrangement having at least two electrodes positioned to sense and/or pace different chambers of the heart. The electrodes switch from a bipolar configuration to an unipolar configuration in order to verify the point of origin for the cardiac signal and in order to determine whether propagation of the cardiac signal occurs. The apparatus allows simultaneous and timed pacing of left and right chambers.
Description
-CA 022489~2 1998-09-14 Description Dual Chamber Pacing with In erchamber Delay Technical Field The present invention relates to implantable cardiac stimulat-)rs, particularly pacemakers, pulse generators and defibrillators which electrically ~timnl~t~ the heart and particularly to stimulators which stimulate the heart at a plur~lity of locations.
Back~round Ar¢
Pacemakers, defibrillators, and pulse generators may employ various multiple-chamber electrode arrangements in the hearts of patients. Four chamber pacing, for instance, can be used in patients having obstructed cardiomyopathy, DI:~D syndrome, dilated cardiomyopathy, extended intra-atrial or intra-ventricular conduction times, left originated flutters,or atrial fibrillations. In obstructed or dilated cardiomyopathy, one or two electrodes are positioned in the left and/or right atrium and one electrode in the left and/or right ventricle. In this multiple-chamber arrangement, when the electrode in the atrium detects a cardiac signal, one or both of the atrial electrodes may stimnl~te the atria and one or both of the ventricular electrodes may stimnl~te the ventricles. The multiple-chamber electrodes thus work in conjunction to pace and sense all four chambers of the heart.
Other multiple-chamber electrode arrangements are employed in patients as well. Dual chamber pacing, for example, may be used to prevent, detect and/or treat atrial fibrillation. In one possible arrangement, a unipolar lead is positioned in the right atrium, and a bipolar lead is positioned, via the coronary sinus, adjacent to the left atrium. When a bipolar detection between both leads is made, a verification of the origin can be made and if a left sided origin exists, the right atrial lead can immediately stim--l~fe the right atrium. This .~timnl~tion causes the right atrium to depolarize and thus halt propagation of the ectopic signal.
As one disadvantage, prior multiple-chamber electrode arrangements do not determine the origination of a cardiac signal, especially when such signals originate as ectopic or extraneous beats.
A dual chamber pacing system treating atrial arrhythmias, for example, may n0t be able to distinguish between an ectopic flutter origin~ting in the left atrium and a normal conduction signal originating at the SA node. In one study, for example, clinicians used a DDD pacem~ker with patients experiencing chronic atrial fibrillation. The clinicians evaluated the problem of the pacemaker inappropriately sensing spontaneous atrial fibrillations and stated:
Since currently available devices sense primarily amplitude, there is no reliable way for DDD pacem~k~rs to discriminate atrial fibrillation from sinus rhythm. Therefore, there is potential for tracking of atrial fibrillation to the upper rate limit of the pacemaker.
,~S~
3 . CA 022489~2 1998-09-14 C. R. Kerr, et. al, "Atrial Fibrillation: Fact, Controversy, and Future," Clin. Prog.
Electrophysiol. and Pacing, Vol.3, No.5(1985),pp.329-330.
As another disadvantage, prior multiple-chamber electrode arrangements do not track or verify propagation of the cardiac conduction signal and thus may stimulate even during periods of normal conduction. Some dual ~llamber pachlg systems employ two atri~l leads to detect and treat atrial arrhythmia. Pacing, however, may occur in both atria even though the cardiac conduction signal originated at the SA node and would have properly propagated to the left atrium. As such, the atrial leads do not verify whether the cardiac signal properly propagates to the left atrium - in spite of possible normal propagation from the SA node.
For example, EP-A-0 596 316 discloses an implanable cardiac pacemaker with first and second bipolar electrodes, which may also be employed in a unipolar configuration. The device, however, does not switch to unipolar configuration after a cardiac signal is sensed, as disclosed herein. It is not, therefore, able to distinguish the origin of the cardiac signal, as disclosed herein.
It therefore would be advantageous to provide a multiple-chamber electrode arrangement that verifies the origination of a cardiac signal propagating in the hearL of the patient. Such a system would be able to recognize and then distinguish between abnormal signals origin~ting in the ventricles or atria and normal cardiac conduction signals origin~ting at the SA node.
Additionally, it would be advantageous to provide a multiple-chamber electrode arrangement which recognizes a normal cardiac conduction signal origin~ting at the SA node and then verifies whether this signal properly propagates to other chambers in the heart. Such a system would not stimulate ImnPces~rily during proper cardiac conduction. Further, battery longevity of the pacemaker or pulse generator would be enhanced.
Disclosure of Invention The present invention is addressed to an apparatus for determining the originating location of a cardiac signal in the heart of a patient. In addition, once a cardiac signal is detected and its location verified, the present invention confirms depolarization and propagation of the cardiac signal from one chamber of the heart to another adjacent chamber.
The apparatus includes a multiple-chamber electrode arrangement having at least two electrodes placed to sense and/or pace different chambers or areas of the heart. The electrodes initially are in a bipolar configuration for sensing cardiac signals origin~ting in the heart. Once a cardiac signal is sensed, the electrodes imm~ tely switch to a unipolar configuration. In order to verify the point of origin for the cardiac signal, the electrodes then re-sense for the presence of the signal in different chambers of the heart where the electrodes may be located. The immediate detection or non-detection of the cardiac signal at an electrode confirms the origin~ting location of A~E~ D SHEET
j CA 022489~2 1998-09-14 -2~-the signal.
Additionally, the apparatus confirms whether a norrnal cardiac conduction signal origin~ing at the SA node or initiated after a pace in the right atrium propagates from the right atrium to other chambers within the heart. In this regard, once a cardiac signal originates at the SA
lD~ SH~
CA 022489~2 1998-09-14 interval timer 20. Interval timer 18 and pacing interval timer 20 have an output connected individually via lines 22 and 24, respectively, to a corresponding input port of microprocessor 14.
Additionally, an indifferent or ground electrode 25 is referenced outside heart 11 and may be provided, for example, from housing 12 of stim~ tor 10. Electrode 25 is electrically connected to microprocessor 14.
Interval timers 18 and 20 may be external to microprocessor 14, as illustrated, or internal thereto. Additionally, these timers may be conventional up/down counters of the type that are initially loaded with a count value and count up to or down from the count value and output a roll-over bit upon completing the programmed count. The initial count value is loaded into interval timers 18 and 20 on bus 15. Respective roll-over bits are output to microprocessor 14 on lines 22 and 24. Memory 16 preferably includes both ROM and RAM. Generally, ROM stores operating routines, and RAM stores prograrnmable parameters and variables.
Microprocessor 14 preferably also has an input/output port connected to a telemetry interface 26 via line 28. Stim~ tor 10, when implanted, is thus able to receive variable and control parameters from an external programmer and to send data to an external receiver if desired. As such, operating parameters stored within microprocessor 14 may be selectively altered non-invasively. Various suitable telemetry systems are known to those skilled in the art.
Microprocessor input/output ports connect via control line 30 to a ventricular sense amplifier and a ventricular pulse generator, shown at block 32 as a ventricular amplif1er and generator.
Microprocessor input/output ports also connect via control line 34 to an atrial sense amplifier and an atrial pulse gel.eldL~r, shown at block 36 as an atrial amplifier and generator. The atrial sense amplifier detects the occurrences of P-waves, and the ventricular sense amplifier detects the occurrences of R-waves. In addition, pulse parameter data, such as amplitude, width, enable/disable, and pulse initiation codes llan~llliL to the atrial and ventricular pulse genelaLol~.
Stimulator 10 is connectable to have a multiple-chamber electrode arrangement. FIG. 1 shows a four chamber electrode arrangement connected to heart 11 of a patient. Ventricular amplifier and generator 32 is electrically connectable to two leads 40 and 42, and atrial amplifier and generator 36 is electrically connectable to two leads 44 and 46.
Lead 40 is an epicardial or endocardial type lead and connects to heart 11 at the left ventricle 50. Lead 42 is an endocardial type lead and connects to heart 11 in the right ventricle 52. In addition, lead 44 is a J-type lead extending to the right atrium 54, and lead 46 extends to the left atrium 56. Lead 46, for example, may be inserted into heart 11 through right atrium 54 and into the coronary sinus 60 by way of the coronary sinus ostium 62 in order to be positioned to stim~ te the left atrium 56.
CA 022489~2 1998-09-14 W O 97/44090 PCT~US97/08258 node, the present invention senses this signal in the right atrium and then commences timing of a conduction interval. This conduction interval represents the time re~uired for the cardiac signal to properly depolarize from the right atrium to another chamber of the heart. If the conduction interval elapses and the cardiac signal did not propagate to the appropriate chamber, then a therapy is S initi~f~d If, on the other hand, proper propagation occurs, no therapy is initi~ted.
The invention, accordingly, ~ t;s the apparatus and method pos~Pccing the construction, combination of elements, and arrangement of parts which are exemplified in the following detailed description. For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawings.
Brief Description of Drawings FIG. 1 is a block diagram of an implantable cardiac stimnl~t~lr connected to a heart in a multiple-chamber electrode arrangement;
FIG. 2 is a flow diagram of the method and program structure according to the present invention;
FIG. 3A is a srh~.m~tic represPnt~ti~n of a heart employing a first multiple-chamber electrode arrangement;
FIG. 3B is a schematic rep,esenl~lion of a heart employing a second multiple-chamber electrode arrangement;
FIG. 4A is a srhf~m~tic ~ ,.lAlion of a heart employing a bipolar electrode configuration;
FIG. 4B is a schf~m~tic l~.es~ lion of the heart of FIG. 4A employing a unipolar electrode configuration;
FIG. 5A is a s- l~P~ "~ se~ -n of a heart employing a bipolar electrode configuration;
FIG. 5B is a schPm~tic lc~lG~enl~lion of the heart of FIG. SA employing a unipolar electrode configuration;
FIG. 6A is a detailed flow diagram of the program structure according to the present invention; and FIG. 6B is a c~lllhlu~lion of the detailed flow diagram of FIG. 6A.
RP.C~ Mode for C~rryir~E Out the Tnvention FIG. 1 is a block diagram illustrating an implantable cardiac stimnl~tor 10 connected to a heart 11 in a multiple-chamber electrode arrangement. Stim~ tor 10 may be a pacemaker or other implantable pulse generator and comprises an outer conductive housing 12 having control circuitry 13 enclosed therein. Clontrol circuitry 13 includes a microprocessor 14 which provides control and colll~ul~lional facilities for stiml-l~tor 10. Microprocessor 14 has input/output ports connected in a conventional manner via bi-directional bus 15 to memory 16, an interval timer 18, and a pacing j CA 022489~2 1998-09-14 FIG. 1 S}IOWS a multiple-chamber electrode arrangement in which leads 42 and 44 are each positioned within a single chamber of the heart, and leads 40 and 46 are each positioned adjacent a single chamber. Those skilled in the art will recognize that these leads may be in various positions within, about, or adjacent chambers of the heart in order to establish a location for sensing and pacing. FurLller, various methods of iead implantation and fixation also are known Additionally, the present invention may be used with various implantable devices, with stimulator 10 in FIG. 1 illustrating an example of one such device. Stimulator 10, for example, may be a multiprogrammable, bipolar cardiac pulse generator designed to detect and terminate tachycardias and provide bradycardia pacing, such as the "INTERTACH II" or the "MARATHON
II" each manufactured by Sulzer Intermedics Inc. Other possible implantable devices may be directed solely or jointly to tachycardias, bradycardias, defibrillation, or pulse generation.
The overall operating algorithm is more fully illustrated in a discussion of the flow diagrams and figures which follow. The flow diagrams represent the preferred embodiment of the program structure under which the microprocessor operates. The program structure may be written, for example, in a low level computer language and retained in a memory within the microprocessor.
Looking first to FIG. 2, a flow diagram shows an overview of the algorithm. As shown in block 100, electrodes are placed for selected pacing and sensing of the heart. The electrodes may be placed in various dual or multiple-chamber arrangements or configurations depending upon the desired pacing and sensing capabilities needed. Possible multiple-chamber configurations include electrodes positioned in or adjacent to or electrically connected with two, three, or four chambers of the heart.
By way of example, FIGS. 3A and 3B illustrate two different multiple-chamber arrangements. Each of the figures depicts a schematic representation of a heart 104 having a right atrium 106, a left atrium 108, a right ventricle 110, and a left ventricle 112. FIG. 3A has a lead 114A with an electrode 115A positioned in right atrium 106, a lead 116A with an electrode 117A
positioned adjacent left atrium 108, and a lead 118A with an electrode ll9A positioned in right ventricle 110. FIG. 3B shows a lead 114B with electrode 115B in right atrium 106, a lead 116B with electrode 117B adjacent left atrium 108, a lead 118B with electrode l l9B in right ventricle 110, and a lead 120B with electrode 121B adjacent left ventricle 112.
Each of the electrodes in FIGS. 3A and 3B may be positioned in, adjacent to, or electrically connected with a chamber or a selected area of the heart in order to effect sensing cr pacing. In addition, the leads may have various configurations such as endocardial, epicardial, or the like, and may have a single electrode, such as a unipolar lead, or have two electrodes, such as a bipolar lead, ~ 5~E~
CA 022489~2 1998-09-14 W O 97/44090 PCTrUS97/08258 or have numerous electrodes. Further, the electrodes may have various polarity configurations to pace and/or sense in one or more chambers of the heart.
Turning back mo~ne~ ily to FIG. 2, after the leads and corresponding electrodes are placed in the heart per block 100, block 130 shows selection of a bipolar configuration.
FIGS. 4A, 4B, SA, and SB illustrate examples of this bipolar configuration. Each of these figures depicts a heart 104 having a right atrium 106, a left atrium 10~, a right ventricle 110, and a left ventricle 112. Further, an implantable cardiac .$tim~ tor is l. pl.~s.~ ed at 132 and may be, for example, similar to stim~ tf~r 10 described in connection with FIG. 1. Stimulator 132 is generally shown as having a conductive housing 134 and two leads 136 ~xt~n~ling from a header portion 138. Leads 136 may be biruicaled Y-connector leads to accommodate multiple-chamber configurations.
Looking now to FIG. 4A, a bipolar lead 140 is in right atrium 106, and a second bipolar lead 142 is t~-l3~nt left atrium 108. Lead 140 has a tip electrode 144 and a ring electrode 145, and lead 142 has a tip electrode 146 and a ring electrode 147. Leads 140 and 142 are shown in a bipolar configuration since sensing occurs between the two leads. Lines 148 represent the electrom~nPtie field lines between electrodes 144 and 146 in order to illustrate the bipolar configuration Looking to FIG. SA, a bipolar lead 150 is in right atrium 106; a second bipolar lead 152 is in right ventricle 110; and a third lead 153 is in left ventricle 112. Lead 150 has a tip electrode 154 and a ring electrode 155; lead 152 has a tip electrode 156 and a ring electrode 157; and lead 153 has a tip electrode 159. Leads 152 and 153 are shown in a bipolar configuration since sensing occurs between the two leads. Lines 158 represent the electrom~gn~tic field lines between the electrodes 156 and 159 in order to illustrate this bipolar configuration. It will be a~ .,iated that all leads in the figures may have various configurations such as bipolar, unipolar, or other multiple electrode type leads known to those skilled in the art.
Turning back again to FIG. 2, after selection is made to the bipolar configuration, block 170 queries whether a cardiac signal is being sensed. If the answer to this query is negative and no signal is sensed, then the flow diagrarn proceeds to block 172 to initiate a therapy, such as pacing. If, on the other hand, the answer to this query is ~fflrm~tive and a signal is sensed, then block 174 shows a switch to a unipolar conrl~ulaiion. FIGS. 4B and SB illustrate an electrode ~ llg.,lllent which has been switched to a unipolar configuration.
Once in the unipolar configuration, sensing and/or pacing occurs between an electrode positioned to sense and/or pace the heart and a ground or illdirr~ llL electrode. In FIG. 4B, sensing and/or pacing occurs between tip electrode 146 of lead 142 and conductive housing 134 which acts as a ground electrode. An arrow 180 lc~l~selll, the occurrence of this sensing and/or pacing.
.. , e ,~ . t~ t ~
CA 022489~2 1998-09-14 W O 97/44090 PCT~US97/08258 Sensing and/or pacing also could occur between tip electrode 144 of lead 140 and conductive housing 134. In FIG. SB, sensing and/or pacing occurs between tip electrode 156 of lead 152 and conductive housing 134. An arrow 182 lc~sellL~ the oc-:ullcllce of this sensing and/or pacing. Sensing and/or pacing could also occur between tip electrode 159 of lead 153 and conductive housing 134.
Turning back to FIG. 2, once a switch is made to the unipolar configuration, block 186 queries the confirmation of the origin of the cardiac signal. If confirmz~ti~ n is made, then, as shown in block 188, therapy is initi~t~d If confirmation is not made, then, as shown at block 190, the program structure comml~nr~s timing of a conduction interval. Reference is made to all of the FIGS.
Back~round Ar¢
Pacemakers, defibrillators, and pulse generators may employ various multiple-chamber electrode arrangements in the hearts of patients. Four chamber pacing, for instance, can be used in patients having obstructed cardiomyopathy, DI:~D syndrome, dilated cardiomyopathy, extended intra-atrial or intra-ventricular conduction times, left originated flutters,or atrial fibrillations. In obstructed or dilated cardiomyopathy, one or two electrodes are positioned in the left and/or right atrium and one electrode in the left and/or right ventricle. In this multiple-chamber arrangement, when the electrode in the atrium detects a cardiac signal, one or both of the atrial electrodes may stimnl~te the atria and one or both of the ventricular electrodes may stimnl~te the ventricles. The multiple-chamber electrodes thus work in conjunction to pace and sense all four chambers of the heart.
Other multiple-chamber electrode arrangements are employed in patients as well. Dual chamber pacing, for example, may be used to prevent, detect and/or treat atrial fibrillation. In one possible arrangement, a unipolar lead is positioned in the right atrium, and a bipolar lead is positioned, via the coronary sinus, adjacent to the left atrium. When a bipolar detection between both leads is made, a verification of the origin can be made and if a left sided origin exists, the right atrial lead can immediately stim--l~fe the right atrium. This .~timnl~tion causes the right atrium to depolarize and thus halt propagation of the ectopic signal.
As one disadvantage, prior multiple-chamber electrode arrangements do not determine the origination of a cardiac signal, especially when such signals originate as ectopic or extraneous beats.
A dual chamber pacing system treating atrial arrhythmias, for example, may n0t be able to distinguish between an ectopic flutter origin~ting in the left atrium and a normal conduction signal originating at the SA node. In one study, for example, clinicians used a DDD pacem~ker with patients experiencing chronic atrial fibrillation. The clinicians evaluated the problem of the pacemaker inappropriately sensing spontaneous atrial fibrillations and stated:
Since currently available devices sense primarily amplitude, there is no reliable way for DDD pacem~k~rs to discriminate atrial fibrillation from sinus rhythm. Therefore, there is potential for tracking of atrial fibrillation to the upper rate limit of the pacemaker.
,~S~
3 . CA 022489~2 1998-09-14 C. R. Kerr, et. al, "Atrial Fibrillation: Fact, Controversy, and Future," Clin. Prog.
Electrophysiol. and Pacing, Vol.3, No.5(1985),pp.329-330.
As another disadvantage, prior multiple-chamber electrode arrangements do not track or verify propagation of the cardiac conduction signal and thus may stimulate even during periods of normal conduction. Some dual ~llamber pachlg systems employ two atri~l leads to detect and treat atrial arrhythmia. Pacing, however, may occur in both atria even though the cardiac conduction signal originated at the SA node and would have properly propagated to the left atrium. As such, the atrial leads do not verify whether the cardiac signal properly propagates to the left atrium - in spite of possible normal propagation from the SA node.
For example, EP-A-0 596 316 discloses an implanable cardiac pacemaker with first and second bipolar electrodes, which may also be employed in a unipolar configuration. The device, however, does not switch to unipolar configuration after a cardiac signal is sensed, as disclosed herein. It is not, therefore, able to distinguish the origin of the cardiac signal, as disclosed herein.
It therefore would be advantageous to provide a multiple-chamber electrode arrangement that verifies the origination of a cardiac signal propagating in the hearL of the patient. Such a system would be able to recognize and then distinguish between abnormal signals origin~ting in the ventricles or atria and normal cardiac conduction signals origin~ting at the SA node.
Additionally, it would be advantageous to provide a multiple-chamber electrode arrangement which recognizes a normal cardiac conduction signal origin~ting at the SA node and then verifies whether this signal properly propagates to other chambers in the heart. Such a system would not stimulate ImnPces~rily during proper cardiac conduction. Further, battery longevity of the pacemaker or pulse generator would be enhanced.
Disclosure of Invention The present invention is addressed to an apparatus for determining the originating location of a cardiac signal in the heart of a patient. In addition, once a cardiac signal is detected and its location verified, the present invention confirms depolarization and propagation of the cardiac signal from one chamber of the heart to another adjacent chamber.
The apparatus includes a multiple-chamber electrode arrangement having at least two electrodes placed to sense and/or pace different chambers or areas of the heart. The electrodes initially are in a bipolar configuration for sensing cardiac signals origin~ting in the heart. Once a cardiac signal is sensed, the electrodes imm~ tely switch to a unipolar configuration. In order to verify the point of origin for the cardiac signal, the electrodes then re-sense for the presence of the signal in different chambers of the heart where the electrodes may be located. The immediate detection or non-detection of the cardiac signal at an electrode confirms the origin~ting location of A~E~ D SHEET
j CA 022489~2 1998-09-14 -2~-the signal.
Additionally, the apparatus confirms whether a norrnal cardiac conduction signal origin~ing at the SA node or initiated after a pace in the right atrium propagates from the right atrium to other chambers within the heart. In this regard, once a cardiac signal originates at the SA
lD~ SH~
CA 022489~2 1998-09-14 interval timer 20. Interval timer 18 and pacing interval timer 20 have an output connected individually via lines 22 and 24, respectively, to a corresponding input port of microprocessor 14.
Additionally, an indifferent or ground electrode 25 is referenced outside heart 11 and may be provided, for example, from housing 12 of stim~ tor 10. Electrode 25 is electrically connected to microprocessor 14.
Interval timers 18 and 20 may be external to microprocessor 14, as illustrated, or internal thereto. Additionally, these timers may be conventional up/down counters of the type that are initially loaded with a count value and count up to or down from the count value and output a roll-over bit upon completing the programmed count. The initial count value is loaded into interval timers 18 and 20 on bus 15. Respective roll-over bits are output to microprocessor 14 on lines 22 and 24. Memory 16 preferably includes both ROM and RAM. Generally, ROM stores operating routines, and RAM stores prograrnmable parameters and variables.
Microprocessor 14 preferably also has an input/output port connected to a telemetry interface 26 via line 28. Stim~ tor 10, when implanted, is thus able to receive variable and control parameters from an external programmer and to send data to an external receiver if desired. As such, operating parameters stored within microprocessor 14 may be selectively altered non-invasively. Various suitable telemetry systems are known to those skilled in the art.
Microprocessor input/output ports connect via control line 30 to a ventricular sense amplifier and a ventricular pulse generator, shown at block 32 as a ventricular amplif1er and generator.
Microprocessor input/output ports also connect via control line 34 to an atrial sense amplifier and an atrial pulse gel.eldL~r, shown at block 36 as an atrial amplifier and generator. The atrial sense amplifier detects the occurrences of P-waves, and the ventricular sense amplifier detects the occurrences of R-waves. In addition, pulse parameter data, such as amplitude, width, enable/disable, and pulse initiation codes llan~llliL to the atrial and ventricular pulse genelaLol~.
Stimulator 10 is connectable to have a multiple-chamber electrode arrangement. FIG. 1 shows a four chamber electrode arrangement connected to heart 11 of a patient. Ventricular amplifier and generator 32 is electrically connectable to two leads 40 and 42, and atrial amplifier and generator 36 is electrically connectable to two leads 44 and 46.
Lead 40 is an epicardial or endocardial type lead and connects to heart 11 at the left ventricle 50. Lead 42 is an endocardial type lead and connects to heart 11 in the right ventricle 52. In addition, lead 44 is a J-type lead extending to the right atrium 54, and lead 46 extends to the left atrium 56. Lead 46, for example, may be inserted into heart 11 through right atrium 54 and into the coronary sinus 60 by way of the coronary sinus ostium 62 in order to be positioned to stim~ te the left atrium 56.
CA 022489~2 1998-09-14 W O 97/44090 PCT~US97/08258 node, the present invention senses this signal in the right atrium and then commences timing of a conduction interval. This conduction interval represents the time re~uired for the cardiac signal to properly depolarize from the right atrium to another chamber of the heart. If the conduction interval elapses and the cardiac signal did not propagate to the appropriate chamber, then a therapy is S initi~f~d If, on the other hand, proper propagation occurs, no therapy is initi~ted.
The invention, accordingly, ~ t;s the apparatus and method pos~Pccing the construction, combination of elements, and arrangement of parts which are exemplified in the following detailed description. For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawings.
Brief Description of Drawings FIG. 1 is a block diagram of an implantable cardiac stimnl~t~lr connected to a heart in a multiple-chamber electrode arrangement;
FIG. 2 is a flow diagram of the method and program structure according to the present invention;
FIG. 3A is a srh~.m~tic represPnt~ti~n of a heart employing a first multiple-chamber electrode arrangement;
FIG. 3B is a schematic rep,esenl~lion of a heart employing a second multiple-chamber electrode arrangement;
FIG. 4A is a srhf~m~tic ~ ,.lAlion of a heart employing a bipolar electrode configuration;
FIG. 4B is a schf~m~tic l~.es~ lion of the heart of FIG. 4A employing a unipolar electrode configuration;
FIG. 5A is a s- l~P~ "~ se~ -n of a heart employing a bipolar electrode configuration;
FIG. 5B is a schPm~tic lc~lG~enl~lion of the heart of FIG. SA employing a unipolar electrode configuration;
FIG. 6A is a detailed flow diagram of the program structure according to the present invention; and FIG. 6B is a c~lllhlu~lion of the detailed flow diagram of FIG. 6A.
RP.C~ Mode for C~rryir~E Out the Tnvention FIG. 1 is a block diagram illustrating an implantable cardiac stimnl~tor 10 connected to a heart 11 in a multiple-chamber electrode arrangement. Stim~ tor 10 may be a pacemaker or other implantable pulse generator and comprises an outer conductive housing 12 having control circuitry 13 enclosed therein. Clontrol circuitry 13 includes a microprocessor 14 which provides control and colll~ul~lional facilities for stiml-l~tor 10. Microprocessor 14 has input/output ports connected in a conventional manner via bi-directional bus 15 to memory 16, an interval timer 18, and a pacing j CA 022489~2 1998-09-14 FIG. 1 S}IOWS a multiple-chamber electrode arrangement in which leads 42 and 44 are each positioned within a single chamber of the heart, and leads 40 and 46 are each positioned adjacent a single chamber. Those skilled in the art will recognize that these leads may be in various positions within, about, or adjacent chambers of the heart in order to establish a location for sensing and pacing. FurLller, various methods of iead implantation and fixation also are known Additionally, the present invention may be used with various implantable devices, with stimulator 10 in FIG. 1 illustrating an example of one such device. Stimulator 10, for example, may be a multiprogrammable, bipolar cardiac pulse generator designed to detect and terminate tachycardias and provide bradycardia pacing, such as the "INTERTACH II" or the "MARATHON
II" each manufactured by Sulzer Intermedics Inc. Other possible implantable devices may be directed solely or jointly to tachycardias, bradycardias, defibrillation, or pulse generation.
The overall operating algorithm is more fully illustrated in a discussion of the flow diagrams and figures which follow. The flow diagrams represent the preferred embodiment of the program structure under which the microprocessor operates. The program structure may be written, for example, in a low level computer language and retained in a memory within the microprocessor.
Looking first to FIG. 2, a flow diagram shows an overview of the algorithm. As shown in block 100, electrodes are placed for selected pacing and sensing of the heart. The electrodes may be placed in various dual or multiple-chamber arrangements or configurations depending upon the desired pacing and sensing capabilities needed. Possible multiple-chamber configurations include electrodes positioned in or adjacent to or electrically connected with two, three, or four chambers of the heart.
By way of example, FIGS. 3A and 3B illustrate two different multiple-chamber arrangements. Each of the figures depicts a schematic representation of a heart 104 having a right atrium 106, a left atrium 108, a right ventricle 110, and a left ventricle 112. FIG. 3A has a lead 114A with an electrode 115A positioned in right atrium 106, a lead 116A with an electrode 117A
positioned adjacent left atrium 108, and a lead 118A with an electrode ll9A positioned in right ventricle 110. FIG. 3B shows a lead 114B with electrode 115B in right atrium 106, a lead 116B with electrode 117B adjacent left atrium 108, a lead 118B with electrode l l9B in right ventricle 110, and a lead 120B with electrode 121B adjacent left ventricle 112.
Each of the electrodes in FIGS. 3A and 3B may be positioned in, adjacent to, or electrically connected with a chamber or a selected area of the heart in order to effect sensing cr pacing. In addition, the leads may have various configurations such as endocardial, epicardial, or the like, and may have a single electrode, such as a unipolar lead, or have two electrodes, such as a bipolar lead, ~ 5~E~
CA 022489~2 1998-09-14 W O 97/44090 PCTrUS97/08258 or have numerous electrodes. Further, the electrodes may have various polarity configurations to pace and/or sense in one or more chambers of the heart.
Turning back mo~ne~ ily to FIG. 2, after the leads and corresponding electrodes are placed in the heart per block 100, block 130 shows selection of a bipolar configuration.
FIGS. 4A, 4B, SA, and SB illustrate examples of this bipolar configuration. Each of these figures depicts a heart 104 having a right atrium 106, a left atrium 10~, a right ventricle 110, and a left ventricle 112. Further, an implantable cardiac .$tim~ tor is l. pl.~s.~ ed at 132 and may be, for example, similar to stim~ tf~r 10 described in connection with FIG. 1. Stimulator 132 is generally shown as having a conductive housing 134 and two leads 136 ~xt~n~ling from a header portion 138. Leads 136 may be biruicaled Y-connector leads to accommodate multiple-chamber configurations.
Looking now to FIG. 4A, a bipolar lead 140 is in right atrium 106, and a second bipolar lead 142 is t~-l3~nt left atrium 108. Lead 140 has a tip electrode 144 and a ring electrode 145, and lead 142 has a tip electrode 146 and a ring electrode 147. Leads 140 and 142 are shown in a bipolar configuration since sensing occurs between the two leads. Lines 148 represent the electrom~nPtie field lines between electrodes 144 and 146 in order to illustrate the bipolar configuration Looking to FIG. SA, a bipolar lead 150 is in right atrium 106; a second bipolar lead 152 is in right ventricle 110; and a third lead 153 is in left ventricle 112. Lead 150 has a tip electrode 154 and a ring electrode 155; lead 152 has a tip electrode 156 and a ring electrode 157; and lead 153 has a tip electrode 159. Leads 152 and 153 are shown in a bipolar configuration since sensing occurs between the two leads. Lines 158 represent the electrom~gn~tic field lines between the electrodes 156 and 159 in order to illustrate this bipolar configuration. It will be a~ .,iated that all leads in the figures may have various configurations such as bipolar, unipolar, or other multiple electrode type leads known to those skilled in the art.
Turning back again to FIG. 2, after selection is made to the bipolar configuration, block 170 queries whether a cardiac signal is being sensed. If the answer to this query is negative and no signal is sensed, then the flow diagrarn proceeds to block 172 to initiate a therapy, such as pacing. If, on the other hand, the answer to this query is ~fflrm~tive and a signal is sensed, then block 174 shows a switch to a unipolar conrl~ulaiion. FIGS. 4B and SB illustrate an electrode ~ llg.,lllent which has been switched to a unipolar configuration.
Once in the unipolar configuration, sensing and/or pacing occurs between an electrode positioned to sense and/or pace the heart and a ground or illdirr~ llL electrode. In FIG. 4B, sensing and/or pacing occurs between tip electrode 146 of lead 142 and conductive housing 134 which acts as a ground electrode. An arrow 180 lc~l~selll, the occurrence of this sensing and/or pacing.
.. , e ,~ . t~ t ~
CA 022489~2 1998-09-14 W O 97/44090 PCT~US97/08258 Sensing and/or pacing also could occur between tip electrode 144 of lead 140 and conductive housing 134. In FIG. SB, sensing and/or pacing occurs between tip electrode 156 of lead 152 and conductive housing 134. An arrow 182 lc~sellL~ the oc-:ullcllce of this sensing and/or pacing. Sensing and/or pacing could also occur between tip electrode 159 of lead 153 and conductive housing 134.
Turning back to FIG. 2, once a switch is made to the unipolar configuration, block 186 queries the confirmation of the origin of the cardiac signal. If confirmz~ti~ n is made, then, as shown in block 188, therapy is initi~t~d If confirmation is not made, then, as shown at block 190, the program structure comml~nr~s timing of a conduction interval. Reference is made to all of the FIGS.
3, 4, and 5 to illustrate the operation of blocks 186, 188, and 190.
In FIG. 4A, for example, as soon as a cardiac signal is initially ~l~ tect~cl in the bipolar configuration, the origination of that signal may not be known. For example, lead 140 in left atrium 108 may detect a cardiac signal. This signal, however, may have originated in the SA node in right atrium 106. Alternatively, this signal may have originated elsewhere, for instance as an ectopic signal in left atrium 108. Similarly, in FIG. 3B, as soon as a cardiac signal is detected in the bipolar mode, the origin~ting location of that signal may not be known. For instance, lead 118B in FIG. 3B
may detect a signal which c(.".l..~ ed as an ectopic beat in left ventricle 112 and propagated to right ventricle 110. Alternatively, the signal may have originated from right ventricle 110 and propagated to the SA node.
In order to confirm where the cardiac signal origin~t~, the electrode arrangement is immt ~ tely switched from the bipolar configuration to the unipolar configuration. Switching from the bipolar to the unipolar configuration verifies the origination of the signal. Looking to FIG. 4A, if, for example, a cardiac signal originated in left atrium 108 as an arrhythmia, this signal would be detected in the bipolar configuration. A switch then would occur to the unipolar configuration.
Once in the unipolar configuration, lead 140 in left atrium 108 would imme~ tely detect the presence of the signal. The immf ~ t~ detection of this signal ~;Ollrl~ s after dis~ ion from the ventricle the signal originated in the left atrium. In turn, as shown in block 188, the stim~ tor would initiate a therapy, such as pacing. Suppose instead, an intrinsic ca}diac signal originated in right atrium 106 at the SA node. This signal would be detected in the bipolar configuration, and a switch would occur to the unipolar configuration. Once in the unipolar configuration, lead 140 in left atrium 108, however, would not imm~ t~ly detect the presence of the signal since a definitive amount of time is required for the signal to propagate to left atrium 108. This delay in time would confirm the signal originated in right atrium 106.
Turning back again to FlCi.2, once a switch is made to the unipolar configuration, the im~ tor comm~nr~c to time a c-)nrlnction interval, as shown in block 190. Next, block 192 queries J CA 022489~2 1998-09-14 whether depolarization or propagation has occurred. If the answer to this query is negative, pacing is initi~te~l, as shown in block 194. If the answer to this query is positive, no pacing is initiated, as shown in block 196. The program structure then loops back along line 198 to block 130. Reference is made to all of the FIGS. 3, 4, and 5 for illustration purposes.
In FIGS. 4A and-4B, for cxample, if the answer ~G block 186 is negative ~nd a signal originates in right atrium 106, then the stim~ tor commences to time a conduction interval, as shown in block 190. In FIGS. 4A and 4B, this interval is equal to an intra-atrial conduction time (i.e., the time required for a P-wave cardiac signal to propagate from right atrium 106 to left atrium 108).
If the cardiac signal properly propagates and is detected in left atrium 108 before the end of the intra-atrial conduction time, then no pacing or therapy is initi~ted, as shown in block 196. If, however, proper propagation does not occur and no cardiac signal is detected in left atrium 108, then pacing is initiated, as shown in block 194.
FIGS. 5A and 5B illustrate yet another example. If the answer to block 186 is negative and a signal originates in right atrium 106, then the stimlll~tor commen(~e~ to time a conduction interval as shown in block 190 In FIG. SA, this interval is a ventricular conduction time (i.e., the time required for an intrinsic cardiac conduction signal to properly propagate from the SA node to right ventricle 110). If the cardiac signal properly propagates and is detected in right ventricle 110 before the end of the conduction time, then no pacing or therapy is initiated. ~ If, however, proper propagation does not occur and no cardiac signal is detected in right ventricle 110, then pacing is initiated.
FIG. 3B illustrates another example. If the answer to block 186 is negative and a signal originates in right atrium 106, then the stimlll~tor commenees to time a conduction interval as shown in block 190. If the cardiac signal properly propagates and is detected in left ventricle 112 before the end of the conduction time, then no pacing therapy is initi~te~d, as shown in block 196. If, however, proper propagation does not occur and no cardiac signal is detected in left ventricle 112, then pacing is initiated, as shown in block 194.
As one advantage, the present invention may be utilized to treat cardiac disorders. For example, the left atrium of the heart may be stimlll~ted after the intra-atrial conduction time elapses to assure that the left atrium contracts before the left ventricle. Stimnl~tion of the left atrium before the left ventricle aids to prevent DDD syndrome. Additionally, the left atrium may be pre-stimlll~ted before stimlll:~ti~n of the right atrium. Stirnulation of the left atrium before tile right atrium aids to reduce the occurrence of a potential atrial arrhythmia.
FIGS. 6A and 6B illustrate a detailed flow diagram of the program structure. The program structure commences at block 200 with start ventricular-atrial (V-A) time.
ND~
CA 022489~2 1998-09-14 W O 97/44090 rCT~US97/082S8 During the V-A time, block 202 shows a check for atrial sense and a check for ventricular sense.
The atrial sensing is done in a bipolar configuration, and the ventricular sensing is done in either a - bipolar or unipolar configuration. Next, block 204 queries whether a cardiac signal is sensed in the ventricle. If the answer to this query is ~fflrm:~ive, the cardiac signal sensed in the ventricle is considered an extraneous or ectopic beat, and the program structure proceeds to section F.
At section F, block 206 queries whether the ventricular switch is set on. If the answer to this query is ~ffirm~tive, then the ventricle ;s switched to unipolar sense as shown in block 208. Next block 210 queries whether the ventricle is reco,lrlllllillg sensing in the unipolar configuration. If the answer to this query is affirmative, then the program structure proceeds to section D and to block 200. If the answer to this query is negative, then, as at block 212, an intra-ventricular conduction time (IVCT) comm~n~es. Block 214 then queries whether the IVCT has ended. If the answer to this query is negative, then the program structure loops back along line 215 to block 210. If, on the other hand, the answer is ~ffirm~tive, the program structure proceeds to section C.
Turning back now to block 204, if the answer to the query is negative, then the program structure proceeds to block 220. This block queries whether a cardiac signal is sensed in the atrium.
If the answer to this query is positive, then the program structure proceeds to section B. If the answer is negative, then block 222 queries whether the V-A time has elapsed. If the answer to this query is negative, then the program ~LIu~;Lult~ loops back along line 223 to block 200. If the answer to the query is ;~ rr~ e, then a switch is made to the unipolar configuration and then stimulation is initi~tçrl, as shown in block 224. After stim~ tion occurs in block 224, block 226 shows collllll~?n~illg the intra-atrial conduction time (IACT). After block 226, the program structure continues to section L.
At section L, block 230 queries whether a commitmPnt to pacing exists. If the answer is negative, then block 231 queries whether a cardiac signal is sensed in the atriurn while in the unipolar configuration. If the answer is ~fflrm~tive, then block 232 shows to cornmence the A-V
time. Next, block 234 queries whether a cardiac signal is sensed in the ventricle while in either an unipolar or bipolar configuration. If the answer to this query is affirmative, then the program structure proceeds to section F. As noted at section F, block 206 queries whether the ventricular switch is on. If the answer is negative, the program structure proceeds to block 235. Block 235 queries whether the ventricular trigger mode is on. If the answer to this query is positive, the program structure proceeds to section C. If the answer is negative, the program structure proceeds to section D.
If the answer to block 234 is negative, block 236 queries whether the AV time has elapsed.
If the time has not elapsed, then the program structure loops back along line 237 to block 232. If CA 022489~2 1998-09-14 the time has elapsed7 then block 238 queries whether the dynamic ventricular tracking limit (DVTL) time has elapsed; for further discussion on DVTL, see U.S. Patent ~o. 5,609,613 entitled "Improved Control of Pacing Rate in Dual-Chamber, Rate Adaptive Pacemakers. " If the answer to this query is negative, then the program structure proceeds to olock 239 and ~hen loops back along line 210 to block 238. Block 239 holds pacing for a pre-determined time of V-V. If the answer to block 238 is positive, then the program structure proceeds to section C. At section C, block 242 shows s~im~ fion of the ventricle in either the unipolar or bipolar configuration.
Looking back now to block 230, if the answer to this query is af~lrmative, then block 244 queries whether the IACT has elapsed. If the answer to this_query is negative, then the program structure proceeds to block 231. If the answer is affirmative, then the program structure proceeds to section E.
At section E, block 250 shows stim~ ion of the atrium in the bipolar configuration. Next the program structure commences the A-V time, as shown in block 252. Block 254 then queries whether a cardiac signal is sensed in the ventricle while in the bipolar or unipolar configuration. If the answer to this query is ~ffirm~ive and a ventricular event is sensed, then the program structure proceeds to section F. If the answer is negative, block 256 queries whether the A-V time has elapsed. If the time has not elapsed, then the progra.-n structure loops back along to line 258 to block 252 If the time has elapsed, the program structure proceeds to block 242 which shows stimulation of the ventricle Turning back to block 220, if the answer to this query is affirmative, then the program structure proceeds to section B. At section B, block 260 queries whether the switch is on. If the answer is negative, then the program structure proceeds to block 262. Block 262 queries whether the atrial trigger mode is on. If the answer is affirmative, then the program structure proceeds to section E and block 250. If the answer is negative, then the program structure proceeds to section K and block 232.
Looking back to the query of block 260, if the answer is affirmative, then a switch is made to atrial sensing in the unipolar configuration, as shown at block 264. Then, at block 266, the program structure runs switch time. Block 268 then queries whether a cardiac signal is sensed in the atrium while in unipolar configuration. If the answer is affirmative, then block 270 queries whether a cardiac signal is sensed in the ventricle. If a signal in the ventricle is sensed, the program structure proceeds to section F and block 206. If no signal is sensed, the program structure proceeds to section E and block 250.
Turning back to the query of block 268, if the answer is negative and no cardiac signal is sensed in the atrium, then block 272 queries whether the switch time has elapsed. If this time has o S~
', CA 02248952 1998-09-14 not elapsed, then the program structure proceeds to block 268. If this time has elapsed, block 274 commences to run the IACT with either the left atrium or the right atrium.
h~EN~)ED StlEEr
In FIG. 4A, for example, as soon as a cardiac signal is initially ~l~ tect~cl in the bipolar configuration, the origination of that signal may not be known. For example, lead 140 in left atrium 108 may detect a cardiac signal. This signal, however, may have originated in the SA node in right atrium 106. Alternatively, this signal may have originated elsewhere, for instance as an ectopic signal in left atrium 108. Similarly, in FIG. 3B, as soon as a cardiac signal is detected in the bipolar mode, the origin~ting location of that signal may not be known. For instance, lead 118B in FIG. 3B
may detect a signal which c(.".l..~ ed as an ectopic beat in left ventricle 112 and propagated to right ventricle 110. Alternatively, the signal may have originated from right ventricle 110 and propagated to the SA node.
In order to confirm where the cardiac signal origin~t~, the electrode arrangement is immt ~ tely switched from the bipolar configuration to the unipolar configuration. Switching from the bipolar to the unipolar configuration verifies the origination of the signal. Looking to FIG. 4A, if, for example, a cardiac signal originated in left atrium 108 as an arrhythmia, this signal would be detected in the bipolar configuration. A switch then would occur to the unipolar configuration.
Once in the unipolar configuration, lead 140 in left atrium 108 would imme~ tely detect the presence of the signal. The immf ~ t~ detection of this signal ~;Ollrl~ s after dis~ ion from the ventricle the signal originated in the left atrium. In turn, as shown in block 188, the stim~ tor would initiate a therapy, such as pacing. Suppose instead, an intrinsic ca}diac signal originated in right atrium 106 at the SA node. This signal would be detected in the bipolar configuration, and a switch would occur to the unipolar configuration. Once in the unipolar configuration, lead 140 in left atrium 108, however, would not imm~ t~ly detect the presence of the signal since a definitive amount of time is required for the signal to propagate to left atrium 108. This delay in time would confirm the signal originated in right atrium 106.
Turning back again to FlCi.2, once a switch is made to the unipolar configuration, the im~ tor comm~nr~c to time a c-)nrlnction interval, as shown in block 190. Next, block 192 queries J CA 022489~2 1998-09-14 whether depolarization or propagation has occurred. If the answer to this query is negative, pacing is initi~te~l, as shown in block 194. If the answer to this query is positive, no pacing is initiated, as shown in block 196. The program structure then loops back along line 198 to block 130. Reference is made to all of the FIGS. 3, 4, and 5 for illustration purposes.
In FIGS. 4A and-4B, for cxample, if the answer ~G block 186 is negative ~nd a signal originates in right atrium 106, then the stim~ tor commences to time a conduction interval, as shown in block 190. In FIGS. 4A and 4B, this interval is equal to an intra-atrial conduction time (i.e., the time required for a P-wave cardiac signal to propagate from right atrium 106 to left atrium 108).
If the cardiac signal properly propagates and is detected in left atrium 108 before the end of the intra-atrial conduction time, then no pacing or therapy is initi~ted, as shown in block 196. If, however, proper propagation does not occur and no cardiac signal is detected in left atrium 108, then pacing is initiated, as shown in block 194.
FIGS. 5A and 5B illustrate yet another example. If the answer to block 186 is negative and a signal originates in right atrium 106, then the stimlll~tor commen(~e~ to time a conduction interval as shown in block 190 In FIG. SA, this interval is a ventricular conduction time (i.e., the time required for an intrinsic cardiac conduction signal to properly propagate from the SA node to right ventricle 110). If the cardiac signal properly propagates and is detected in right ventricle 110 before the end of the conduction time, then no pacing or therapy is initiated. ~ If, however, proper propagation does not occur and no cardiac signal is detected in right ventricle 110, then pacing is initiated.
FIG. 3B illustrates another example. If the answer to block 186 is negative and a signal originates in right atrium 106, then the stimlll~tor commenees to time a conduction interval as shown in block 190. If the cardiac signal properly propagates and is detected in left ventricle 112 before the end of the conduction time, then no pacing therapy is initi~te~d, as shown in block 196. If, however, proper propagation does not occur and no cardiac signal is detected in left ventricle 112, then pacing is initiated, as shown in block 194.
As one advantage, the present invention may be utilized to treat cardiac disorders. For example, the left atrium of the heart may be stimlll~ted after the intra-atrial conduction time elapses to assure that the left atrium contracts before the left ventricle. Stimnl~tion of the left atrium before the left ventricle aids to prevent DDD syndrome. Additionally, the left atrium may be pre-stimlll~ted before stimlll:~ti~n of the right atrium. Stirnulation of the left atrium before tile right atrium aids to reduce the occurrence of a potential atrial arrhythmia.
FIGS. 6A and 6B illustrate a detailed flow diagram of the program structure. The program structure commences at block 200 with start ventricular-atrial (V-A) time.
ND~
CA 022489~2 1998-09-14 W O 97/44090 rCT~US97/082S8 During the V-A time, block 202 shows a check for atrial sense and a check for ventricular sense.
The atrial sensing is done in a bipolar configuration, and the ventricular sensing is done in either a - bipolar or unipolar configuration. Next, block 204 queries whether a cardiac signal is sensed in the ventricle. If the answer to this query is ~fflrm:~ive, the cardiac signal sensed in the ventricle is considered an extraneous or ectopic beat, and the program structure proceeds to section F.
At section F, block 206 queries whether the ventricular switch is set on. If the answer to this query is ~ffirm~tive, then the ventricle ;s switched to unipolar sense as shown in block 208. Next block 210 queries whether the ventricle is reco,lrlllllillg sensing in the unipolar configuration. If the answer to this query is affirmative, then the program structure proceeds to section D and to block 200. If the answer to this query is negative, then, as at block 212, an intra-ventricular conduction time (IVCT) comm~n~es. Block 214 then queries whether the IVCT has ended. If the answer to this query is negative, then the program structure loops back along line 215 to block 210. If, on the other hand, the answer is ~ffirm~tive, the program structure proceeds to section C.
Turning back now to block 204, if the answer to the query is negative, then the program structure proceeds to block 220. This block queries whether a cardiac signal is sensed in the atrium.
If the answer to this query is positive, then the program structure proceeds to section B. If the answer is negative, then block 222 queries whether the V-A time has elapsed. If the answer to this query is negative, then the program ~LIu~;Lult~ loops back along line 223 to block 200. If the answer to the query is ;~ rr~ e, then a switch is made to the unipolar configuration and then stimulation is initi~tçrl, as shown in block 224. After stim~ tion occurs in block 224, block 226 shows collllll~?n~illg the intra-atrial conduction time (IACT). After block 226, the program structure continues to section L.
At section L, block 230 queries whether a commitmPnt to pacing exists. If the answer is negative, then block 231 queries whether a cardiac signal is sensed in the atriurn while in the unipolar configuration. If the answer is ~fflrm~tive, then block 232 shows to cornmence the A-V
time. Next, block 234 queries whether a cardiac signal is sensed in the ventricle while in either an unipolar or bipolar configuration. If the answer to this query is affirmative, then the program structure proceeds to section F. As noted at section F, block 206 queries whether the ventricular switch is on. If the answer is negative, the program structure proceeds to block 235. Block 235 queries whether the ventricular trigger mode is on. If the answer to this query is positive, the program structure proceeds to section C. If the answer is negative, the program structure proceeds to section D.
If the answer to block 234 is negative, block 236 queries whether the AV time has elapsed.
If the time has not elapsed, then the program structure loops back along line 237 to block 232. If CA 022489~2 1998-09-14 the time has elapsed7 then block 238 queries whether the dynamic ventricular tracking limit (DVTL) time has elapsed; for further discussion on DVTL, see U.S. Patent ~o. 5,609,613 entitled "Improved Control of Pacing Rate in Dual-Chamber, Rate Adaptive Pacemakers. " If the answer to this query is negative, then the program structure proceeds to olock 239 and ~hen loops back along line 210 to block 238. Block 239 holds pacing for a pre-determined time of V-V. If the answer to block 238 is positive, then the program structure proceeds to section C. At section C, block 242 shows s~im~ fion of the ventricle in either the unipolar or bipolar configuration.
Looking back now to block 230, if the answer to this query is af~lrmative, then block 244 queries whether the IACT has elapsed. If the answer to this_query is negative, then the program structure proceeds to block 231. If the answer is affirmative, then the program structure proceeds to section E.
At section E, block 250 shows stim~ ion of the atrium in the bipolar configuration. Next the program structure commences the A-V time, as shown in block 252. Block 254 then queries whether a cardiac signal is sensed in the ventricle while in the bipolar or unipolar configuration. If the answer to this query is ~ffirm~ive and a ventricular event is sensed, then the program structure proceeds to section F. If the answer is negative, block 256 queries whether the A-V time has elapsed. If the time has not elapsed, then the progra.-n structure loops back along to line 258 to block 252 If the time has elapsed, the program structure proceeds to block 242 which shows stimulation of the ventricle Turning back to block 220, if the answer to this query is affirmative, then the program structure proceeds to section B. At section B, block 260 queries whether the switch is on. If the answer is negative, then the program structure proceeds to block 262. Block 262 queries whether the atrial trigger mode is on. If the answer is affirmative, then the program structure proceeds to section E and block 250. If the answer is negative, then the program structure proceeds to section K and block 232.
Looking back to the query of block 260, if the answer is affirmative, then a switch is made to atrial sensing in the unipolar configuration, as shown at block 264. Then, at block 266, the program structure runs switch time. Block 268 then queries whether a cardiac signal is sensed in the atrium while in unipolar configuration. If the answer is affirmative, then block 270 queries whether a cardiac signal is sensed in the ventricle. If a signal in the ventricle is sensed, the program structure proceeds to section F and block 206. If no signal is sensed, the program structure proceeds to section E and block 250.
Turning back to the query of block 268, if the answer is negative and no cardiac signal is sensed in the atrium, then block 272 queries whether the switch time has elapsed. If this time has o S~
', CA 02248952 1998-09-14 not elapsed, then the program structure proceeds to block 268. If this time has elapsed, block 274 commences to run the IACT with either the left atrium or the right atrium.
h~EN~)ED StlEEr
Claims (9)
1. An implantable medical device (10) for determining the origin of a cardiac signal in a heart, comprising:
a conductive housing (12);
control circuitry (13) enclosed within said housing;
a first electrode (115) electrically connected to said control circuitry, and electrically connected with a first chamber of said heart;
a second electrode (117, 119) electrically connected to said control circuitry, and electrically connected with a second chamber of said heart:
an indifferent electrode (25) electrically connected to said housing; and said first and second electrodes being in a bipolar configuration, wherein sensing for said cardiac signal occurs between said first and second electrodes;
characterized by said first and second electrodes being switchable (174) to a unipolar configuration after said cardiac signal is sensed in said bipolar configuration, wherein sensing for said cardiac signal occurs between said indifferent and second electrodes.
a conductive housing (12);
control circuitry (13) enclosed within said housing;
a first electrode (115) electrically connected to said control circuitry, and electrically connected with a first chamber of said heart;
a second electrode (117, 119) electrically connected to said control circuitry, and electrically connected with a second chamber of said heart:
an indifferent electrode (25) electrically connected to said housing; and said first and second electrodes being in a bipolar configuration, wherein sensing for said cardiac signal occurs between said first and second electrodes;
characterized by said first and second electrodes being switchable (174) to a unipolar configuration after said cardiac signal is sensed in said bipolar configuration, wherein sensing for said cardiac signal occurs between said indifferent and second electrodes.
2. The implantable medical device of claim 1 in which said second electrode (117, 119) immediately senses for said cardiac signal once said first and second electrodes switch to said unipolar configuration, wherein immediate detection of said cardiac signal at said second electrode (117, 119) verifies said cardiac signal originated from said second chamber and a lack immediate detection of said cardiac signal at said second electrode verifies said cardiac signal originated from said first chamber.
3. The implantable medical device of claim 2 in which said first electrode (115) paces said first chamber if said cardiac signal originates in said second chamber.
4. The implantable medical device of claim 1 in which said control circuitry (13) initiates (194) pacing in said second chamber if said cardiac signal originates in said first chamber and does not propagate to said second chamber before a conduction time interval elapses (192, 194).
5. The implantable medical device of claim 1 in which:
said first and second electrodes (115, 117, 119) switch (174) to said unipolar configuration and immediate detection of said cardiac signal between said indifferent and second electrodes indicates (186) said cardiac signal originated from said second chamber and no immediate detection of said cardiac signal between said indifferent and second electrodes indicates said cardiac signal originated from said first chamber;
said control circuit commences a conduction time interval (190) if said cardiac signal originates in said first chamber, wherein said conduction time interval equals a time for said cardiac signal to conduct from said first chamber to said second chamber; and said control circuit initiates pacing (194) at said second chamber if said cardiac signal is not sensed in said second chamber before said conduction time interval elapses.
said first and second electrodes (115, 117, 119) switch (174) to said unipolar configuration and immediate detection of said cardiac signal between said indifferent and second electrodes indicates (186) said cardiac signal originated from said second chamber and no immediate detection of said cardiac signal between said indifferent and second electrodes indicates said cardiac signal originated from said first chamber;
said control circuit commences a conduction time interval (190) if said cardiac signal originates in said first chamber, wherein said conduction time interval equals a time for said cardiac signal to conduct from said first chamber to said second chamber; and said control circuit initiates pacing (194) at said second chamber if said cardiac signal is not sensed in said second chamber before said conduction time interval elapses.
6. The implantable medical device of any of the foregoing claims having means (14, 32, 36) to detect and terminate tachycardias and to provide bradycardia pacing.
7. The implantable medical device of any of the foregoing claims in which:
said first chamber is the right atrium of said heart;
said second chamber is the left atrium of said heart; and said conduction time interval is equal to an intra-atrial conduction time.
said first chamber is the right atrium of said heart;
said second chamber is the left atrium of said heart; and said conduction time interval is equal to an intra-atrial conduction time.
8 . The implantable medical device of claim 7 in which said second electrode (117) stimulates said left atrium after said intra-atrial conduction time so said left atrium contracts before the left ventricle of said heart.
9. The implantable medical device of claim 7 in which said second electrode (117) stimulates said left atrium before said first electrode (115) stimulates said right atrium in order to reduce occurrence of an atrial arrhythmia in said left and right atria.
Applications Claiming Priority (2)
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US08/651741 | 1996-05-22 | ||
US08/651,741 US5720768A (en) | 1996-05-22 | 1996-05-22 | Dual chamber pacing with interchamber delay |
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CA2248952A1 true CA2248952A1 (en) | 1997-11-27 |
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CA002248952A Abandoned CA2248952A1 (en) | 1996-05-22 | 1997-05-15 | Dual chamber pacing with interchamber delay |
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EP (1) | EP0901397A1 (en) |
JP (1) | JP2000511076A (en) |
CA (1) | CA2248952A1 (en) |
WO (1) | WO1997044090A1 (en) |
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US7167748B2 (en) * | 1996-01-08 | 2007-01-23 | Impulse Dynamics Nv | Electrical muscle controller |
US8825152B2 (en) * | 1996-01-08 | 2014-09-02 | Impulse Dynamics, N.V. | Modulation of intracellular calcium concentration using non-excitatory electrical signals applied to the tissue |
US9289618B1 (en) | 1996-01-08 | 2016-03-22 | Impulse Dynamics Nv | Electrical muscle controller |
ATE290905T1 (en) * | 1996-01-08 | 2005-04-15 | Impulse Dynamics Nv | DEVICE FOR CONTROLLING HEART ACTIVITY USING NON-EXCITING PRE-STIMULATION |
US8321013B2 (en) | 1996-01-08 | 2012-11-27 | Impulse Dynamics, N.V. | Electrical muscle controller and pacing with hemodynamic enhancement |
US6415178B1 (en) * | 1996-09-16 | 2002-07-02 | Impulse Dynamics N.V. | Fencing of cardiac muscles |
US9713723B2 (en) | 1996-01-11 | 2017-07-25 | Impulse Dynamics Nv | Signal delivery through the right ventricular septum |
US7269457B2 (en) * | 1996-04-30 | 2007-09-11 | Medtronic, Inc. | Method and system for vagal nerve stimulation with multi-site cardiac pacing |
US6904318B2 (en) * | 2000-09-26 | 2005-06-07 | Medtronic, Inc. | Method and system for monitoring and controlling systemic and pulmonary circulation during a medical procedure |
US6449507B1 (en) * | 1996-04-30 | 2002-09-10 | Medtronic, Inc. | Method and system for nerve stimulation prior to and during a medical procedure |
US6628987B1 (en) * | 2000-09-26 | 2003-09-30 | Medtronic, Inc. | Method and system for sensing cardiac contractions during vagal stimulation-induced cardiopalegia |
US8036741B2 (en) | 1996-04-30 | 2011-10-11 | Medtronic, Inc. | Method and system for nerve stimulation and cardiac sensing prior to and during a medical procedure |
US20040199209A1 (en) * | 2003-04-07 | 2004-10-07 | Hill Michael R.S. | Method and system for delivery of vasoactive drugs to the heart prior to and during a medical procedure |
US7840264B1 (en) | 1996-08-19 | 2010-11-23 | Mr3 Medical, Llc | System and method for breaking reentry circuits by cooling cardiac tissue |
US7908003B1 (en) | 1996-08-19 | 2011-03-15 | Mr3 Medical Llc | System and method for treating ischemia by improving cardiac efficiency |
FR2760369B1 (en) * | 1997-03-07 | 1999-04-30 | Ela Medical Sa | MULTI-SITE HEART STIMULATOR FOR THE TREATMENT OF HEART FAILURE BY STIMULATION |
US6415180B1 (en) * | 1997-04-04 | 2002-07-02 | Cardiac Pacemakers, Inc. | Device and method for ventricular tracking and pacing |
US6479523B1 (en) * | 1997-08-26 | 2002-11-12 | Emory University | Pharmacologic drug combination in vagal-induced asystole |
US6096064A (en) * | 1997-09-19 | 2000-08-01 | Intermedics Inc. | Four chamber pacer for dilated cardiomyopthy |
FR2770138B1 (en) * | 1997-10-28 | 2000-02-25 | Ela Medical Sa | PROGRAMMABLE MULTI-SITE HEART STIMULATOR |
US6152954A (en) | 1998-07-22 | 2000-11-28 | Cardiac Pacemakers, Inc. | Single pass lead having retractable, actively attached electrode for pacing and sensing |
US6341233B1 (en) * | 1998-03-31 | 2002-01-22 | Biotronik Mess-Und Therapiegerate Gmbh & Co. | Device for maintaining a natural heart rhythm |
US5902324A (en) * | 1998-04-28 | 1999-05-11 | Medtronic, Inc. | Bi-atrial and/or bi-ventricular sequential cardiac pacing systems |
US6122545A (en) * | 1998-04-28 | 2000-09-19 | Medtronic, Inc. | Multiple channel sequential cardiac pacing method |
US6058327A (en) * | 1998-07-09 | 2000-05-02 | Medtronic, Inc. | Implantable device with automatic sensing adjustment |
US6463334B1 (en) | 1998-11-02 | 2002-10-08 | Cardiac Pacemakers, Inc. | Extendable and retractable lead |
US6501990B1 (en) * | 1999-12-23 | 2002-12-31 | Cardiac Pacemakers, Inc. | Extendable and retractable lead having a snap-fit terminal connector |
US6370427B1 (en) * | 1998-07-23 | 2002-04-09 | Intermedics, Inc. | Method and apparatus for dual chamber bi-ventricular pacing and defibrillation |
US6434428B1 (en) * | 1998-07-29 | 2002-08-13 | Pacesetter, Inc. | System and method for optimizing far-field R-wave sensing by switching electrode polarity during atrial capture verification |
DE69925493T2 (en) | 1998-08-17 | 2006-01-26 | Medtronic, Inc., Minneapolis | DEVICE FOR PREVENTING FOREST STYRIUM ARRHYTHMS |
US6243603B1 (en) * | 1998-09-15 | 2001-06-05 | Uab Research Foundation | Methods and apparatus for detecting medical conditions of the heart |
US6292693B1 (en) | 1998-11-06 | 2001-09-18 | Impulse Dynamics N.V. | Contractility enhancement using excitable tissue control and multi-site pacing |
US6496730B1 (en) | 1998-12-29 | 2002-12-17 | Medtronic, Inc. | Multi-site cardiac pacing system having conditional refractory period |
US6456878B1 (en) | 1998-12-29 | 2002-09-24 | Medtronic, Inc. | Cardiac pacing system delivering multi-site pacing in a predetermined sequence triggered by a sense event |
US6477415B1 (en) | 1998-12-29 | 2002-11-05 | Medtronic, Inc. | AV synchronous cardiac pacing system delivering multi-site ventricular pacing triggered by a ventricular sense event during the AV delay |
US6466820B1 (en) | 1998-12-29 | 2002-10-15 | Medtronic, Inc. | Multi-site cardiac pacing system having trigger pace window |
MXPA01007820A (en) * | 1999-02-04 | 2003-06-19 | Technion Res & Dev Foundation | Method and apparatus for maintenance and expansion of hemopoietic stem cells and/or progenitor cells. |
US8700161B2 (en) * | 1999-03-05 | 2014-04-15 | Metacure Limited | Blood glucose level control |
US20040249421A1 (en) * | 2000-09-13 | 2004-12-09 | Impulse Dynamics Nv | Blood glucose level control |
US9101765B2 (en) | 1999-03-05 | 2015-08-11 | Metacure Limited | Non-immediate effects of therapy |
US8019421B2 (en) * | 1999-03-05 | 2011-09-13 | Metacure Limited | Blood glucose level control |
US8346363B2 (en) * | 1999-03-05 | 2013-01-01 | Metacure Limited | Blood glucose level control |
US8666495B2 (en) * | 1999-03-05 | 2014-03-04 | Metacure Limited | Gastrointestinal methods and apparatus for use in treating disorders and controlling blood sugar |
US7840278B1 (en) * | 1999-06-25 | 2010-11-23 | Puskas John D | Devices and methods for vagus nerve stimulation |
US6324425B1 (en) | 1999-07-28 | 2001-11-27 | Medtronic, Inc., | Recharge circuitry for multi-site stimulation of body tissue |
SE9902847D0 (en) | 1999-08-05 | 1999-08-05 | Pacesetter Ab | A cardiac stimulating device |
SE9902848D0 (en) | 1999-08-05 | 1999-08-05 | Pacesetter Ab | A cardiac stimulating device |
US6363288B1 (en) | 1999-08-20 | 2002-03-26 | Pacesetter, Inc. | CS lead with single site sensing and dual site pacing |
AU1049901A (en) | 1999-10-25 | 2001-05-08 | Impulse Dynamics N.V. | Cardiac contractility modulation device having anti-arrhythmic capabilities and a method of operating thereof |
US6993385B1 (en) * | 1999-10-25 | 2006-01-31 | Impulse Dynamics N.V. | Cardiac contractility modulation device having anti-arrhythmic capabilities and a method of operating thereof |
US6421564B1 (en) * | 1999-11-12 | 2002-07-16 | Medtronic, Inc. | Bi-chamber cardiac pacing system employing unipolar left heart chamber lead in combination with bipolar right chamber lead |
US6937895B1 (en) | 2001-08-14 | 2005-08-30 | Pacesetter, Inc. | Multi-site cardiac stimulation device for controlling inter-chamber stimulation delay |
US6539260B1 (en) * | 2000-02-28 | 2003-03-25 | Pacesetter, Inc. | Atrial sensing and pacing using a unipolar atrial electrode |
EP1267992A4 (en) * | 2000-04-06 | 2008-12-10 | Impulse Dynamics Nv | Contractility enhancement using excitable tissue control and multi-site pacing |
US6748261B1 (en) * | 2000-05-08 | 2004-06-08 | Pacesetter, Inc. | Implantable cardiac stimulation device for and method of monitoring progression or regression of heart disease by monitoring interchamber conduction delays |
US20010049543A1 (en) * | 2000-05-15 | 2001-12-06 | Kroll Mark W. | Method and apparatus for biventricular stimulation and capture monitoring |
US6493586B1 (en) | 2000-08-30 | 2002-12-10 | Cardiac Pacemakers, Inc. | Site reversion in cardiac rhythm management |
US6584362B1 (en) | 2000-08-30 | 2003-06-24 | Cardiac Pacemakers, Inc. | Leads for pacing and/or sensing the heart from within the coronary veins |
US6487446B1 (en) * | 2000-09-26 | 2002-11-26 | Medtronic, Inc. | Method and system for spinal cord stimulation prior to and during a medical procedure |
SE0004240D0 (en) | 2000-11-17 | 2000-11-17 | St Jude Medical | A cardiac stimulating device |
US6574506B2 (en) * | 2000-12-26 | 2003-06-03 | Cardiac Pacemakers, Inc. | System and method for timing synchronized pacing |
US7130682B2 (en) | 2000-12-26 | 2006-10-31 | Cardiac Pacemakers, Inc. | Pacing and sensing vectors |
US6480740B2 (en) * | 2000-12-26 | 2002-11-12 | Cardiac Pacemakers, Inc. | Safety pacing in multi-site CRM devices |
US6735472B2 (en) * | 2001-01-26 | 2004-05-11 | Pacesetter, Inc. | Method of defibrillating a heart with electrode configurations including a left ventricular defibrillation electrode |
US6477417B1 (en) | 2001-04-12 | 2002-11-05 | Pacesetter, Inc. | System and method for automatically selecting electrode polarity during sensing and stimulation |
US7058443B2 (en) * | 2001-04-26 | 2006-06-06 | Medtronic, Inc. | Diagnostic features in biatrial and biventricular pacing systems |
US6654639B1 (en) * | 2001-05-07 | 2003-11-25 | Pacesetter, Inc. | Method and device for multi-chamber cardiac pacing in response to a tachycardia |
US6751504B2 (en) | 2001-05-25 | 2004-06-15 | Pacesetter, Inc. | System and method for bi-chamber stimulation using dynamically adapted interpulse delay |
US6804555B2 (en) | 2001-06-29 | 2004-10-12 | Medtronic, Inc. | Multi-site ventricular pacing system measuring QRS duration |
US6760622B2 (en) * | 2001-07-03 | 2004-07-06 | Pacesetter, Inc. | Implantable multi-chamber cardiac stimulation device with sensing vectors |
US6668194B2 (en) | 2001-07-16 | 2003-12-23 | Medtronic, Inc. | Method and apparatus for monitoring conduction times in a bi-chamber pacing system |
US6745081B1 (en) * | 2001-08-31 | 2004-06-01 | Pacesetter, Inc. | Coronary Sinus Cardiac Lead For Stimulating and Sensing The Atria of the Right and Left Heart and System |
US6748268B1 (en) * | 2001-08-31 | 2004-06-08 | Pacesetter, Inc. | Three lead universal pacing and shocking system |
US6721598B1 (en) | 2001-08-31 | 2004-04-13 | Pacesetter, Inc. | Coronary sinus cardiac lead for stimulating and sensing in the right and left heart and system |
US6760619B1 (en) | 2001-08-31 | 2004-07-06 | Pacesetter, Inc. | Two lead universal defibrillation, pacing and sensing system |
US6748277B1 (en) | 2001-10-11 | 2004-06-08 | Pacesetter, Inc. | Medical catheter/lead body design and means of manufacture thereof |
US6871096B2 (en) * | 2001-10-26 | 2005-03-22 | Medtronic, Inc. | System and method for bi-ventricular fusion pacing |
US20050027323A1 (en) * | 2001-10-30 | 2005-02-03 | Medtronic, Inc. | Implantable medical device for monitoring cardiac blood pressure and chamber dimension |
US6795732B2 (en) * | 2001-10-30 | 2004-09-21 | Medtronic, Inc. | Implantable medical device employing sonomicrometer output signals for detection and measurement of cardiac mechanical function |
US6959214B2 (en) | 2001-11-28 | 2005-10-25 | Medtronic, Inc. | Implantable medical device for measuring mechanical heart function |
SE0104337D0 (en) * | 2001-12-19 | 2001-12-19 | St Jude Medical | An implantable heart stimulating device, a system including such a device and a lesser use of the system |
US6950701B2 (en) * | 2001-12-21 | 2005-09-27 | Medtronic, Inc. | Dual-chamber pacemaker system for simultaneous bi-chamber pacing and sensing |
SE0200922D0 (en) * | 2002-03-25 | 2002-03-25 | St Jude Medical | A heart monitoring device, a system including such a device and a lesser use of the system |
SE0200921D0 (en) * | 2002-03-25 | 2002-03-25 | St Jude Medical | A heart monitoring device, a system including such a device and a lesser use of the system |
US6915164B2 (en) * | 2002-04-16 | 2005-07-05 | Pacesetter, Inc. | Automatic capture using independent channels in bi-chamber stimulation |
US7146214B2 (en) * | 2002-04-22 | 2006-12-05 | Medtronic, Inc. | Anti-tachycardia pacing based on multi-site electrograms |
US7212857B2 (en) * | 2002-05-01 | 2007-05-01 | Pacesetter, Inc. | Implantable cardiac device for restoring inter-chamber synchrony and method |
US7110815B2 (en) * | 2002-05-06 | 2006-09-19 | Cardiac Pacemakers, Inc. | System and method for providing temporary stimulation therapy to optimize chronic electrical performance for electrodes used in conjunction with a cardiac rhythm management system |
SE0201822D0 (en) * | 2002-06-14 | 2002-06-14 | St Jude Medical | A heart monitoring and stimulating device, a system including such a device and use of the system |
SE0202347D0 (en) * | 2002-07-30 | 2002-07-30 | St Jude Medical | A heart monitoring device, a system including such a device and use of the system |
CA2508800A1 (en) | 2002-12-11 | 2004-06-24 | Proteus Biomedical, Inc. | Method and system for monitoring and treating hemodynamic parameters |
SE0203727D0 (en) * | 2002-12-16 | 2002-12-16 | St Jude Medical | An Implantable heart stimulation device, a system including such a device and use of the system |
SE0203726D0 (en) * | 2002-12-16 | 2002-12-16 | St Jude Medical | An Implantable heart stimulating device, a system including such a device and use of the system |
SE0203728D0 (en) * | 2002-12-16 | 2002-12-16 | St Jude Medical | An Implantable heart stimulating device, a system including such a device and use of the system |
EP1585442A4 (en) * | 2003-01-24 | 2006-04-26 | Proteus Biomedical Inc | Method and system for remote hemodynamic monitoring |
EP1585575A4 (en) | 2003-01-24 | 2011-02-09 | Proteus Biomedical Inc | Methods and apparatus for enhancing cardiac pacing |
US7204798B2 (en) * | 2003-01-24 | 2007-04-17 | Proteus Biomedical, Inc. | Methods and systems for measuring cardiac parameters |
US7372455B2 (en) | 2003-02-10 | 2008-05-13 | N-Trig Ltd. | Touch detection for a digitizer |
SE0300446D0 (en) * | 2003-02-18 | 2003-02-18 | St Jude Medical | An implantable heart stimulating device, a system including such a device and use of the system |
US11439815B2 (en) | 2003-03-10 | 2022-09-13 | Impulse Dynamics Nv | Protein activity modification |
WO2004080533A1 (en) * | 2003-03-10 | 2004-09-23 | Impulse Dynamics Nv | Apparatus and method for delivering electrical signals to modify gene expression in cardiac tissue |
US6889083B2 (en) * | 2003-04-21 | 2005-05-03 | Medtronic, Inc. | Atrial tracking recovery to restore cardiac resynchronization therapy in dual chamber tracking modes |
US7233826B2 (en) * | 2003-04-25 | 2007-06-19 | Medtronic, Inc. | Bi-ventricular and single-ventricle pacing |
SE0301743D0 (en) * | 2003-06-12 | 2003-06-12 | St Jude Medical | A heart stimulating device, a system including such a device and use of the system |
US8792985B2 (en) * | 2003-07-21 | 2014-07-29 | Metacure Limited | Gastrointestinal methods and apparatus for use in treating disorders and controlling blood sugar |
US7027866B2 (en) | 2003-07-29 | 2006-04-11 | Medtronic, Inc. | Mechanically-based interval optimization for a biventricular pacing engine |
US7203540B2 (en) * | 2003-12-22 | 2007-04-10 | Cardiac Pacemakers, Inc. | Method and system for setting cardiac resynchronization therapy parameters |
US7123960B2 (en) | 2003-12-22 | 2006-10-17 | Cardiac Pacemakers, Inc. | Method and system for delivering cardiac resynchronization therapy with variable atrio-ventricular delay |
US8548583B2 (en) * | 2004-03-10 | 2013-10-01 | Impulse Dynamics Nv | Protein activity modification |
US11779768B2 (en) | 2004-03-10 | 2023-10-10 | Impulse Dynamics Nv | Protein activity modification |
US8352031B2 (en) * | 2004-03-10 | 2013-01-08 | Impulse Dynamics Nv | Protein activity modification |
DE202004009224U1 (en) * | 2004-06-14 | 2004-08-12 | Isra Vision Systems Ag | Sensor for measuring the surface of an object |
EP1799101A4 (en) | 2004-09-02 | 2008-11-19 | Proteus Biomedical Inc | Methods and apparatus for tissue activation and monitoring |
WO2006105474A2 (en) * | 2005-03-31 | 2006-10-05 | Proteus Biomedical, Inc. | Automated optimization of multi-electrode pacing for cardiac resynchronization |
EP1827571B1 (en) | 2004-12-09 | 2016-09-07 | Impulse Dynamics NV | Protein activity modification |
US9821158B2 (en) | 2005-02-17 | 2017-11-21 | Metacure Limited | Non-immediate effects of therapy |
US7840266B2 (en) * | 2005-03-11 | 2010-11-23 | Cardiac Pacemakers, Inc. | Integrated lead for applying cardiac resynchronization therapy and neural stimulation therapy |
WO2006097934A2 (en) * | 2005-03-18 | 2006-09-21 | Metacure Limited | Pancreas lead |
EP1898999A4 (en) * | 2005-07-01 | 2011-10-19 | Proteus Biomedical Inc | Deployable epicardial electrode and sensor array |
WO2007021804A2 (en) * | 2005-08-12 | 2007-02-22 | Proteus Biomedical, Inc. | Evaluation of depolarization wave conduction velocity |
EP1945301B1 (en) * | 2005-10-31 | 2011-12-14 | St. Jude Medical AB | An implantable heart stimulating device |
ATE537874T1 (en) * | 2005-11-23 | 2012-01-15 | St Jude Medical | IMPLANTABLE HEART STIMULATION DEVICE |
US20100204766A1 (en) * | 2005-12-22 | 2010-08-12 | Mark Zdeblick | Implantable integrated circuit |
US8761882B2 (en) * | 2006-05-16 | 2014-06-24 | St. Jude Medical Ab | Implantable heart stimulating device and method |
US7877142B2 (en) * | 2006-07-05 | 2011-01-25 | Micardia Corporation | Methods and systems for cardiac remodeling via resynchronization |
US7877144B2 (en) * | 2006-07-26 | 2011-01-25 | Medtronic, Inc. | Predicting chronic optimal A-V intervals for biventricular pacing via observed inter-atrial delay |
US9415226B1 (en) | 2007-12-20 | 2016-08-16 | Pacesetter, Inc. | Method and apparatus with anodal capture monitoring |
US8473069B2 (en) * | 2008-02-28 | 2013-06-25 | Proteus Digital Health, Inc. | Integrated circuit implementation and fault control system, device, and method |
US20100121396A1 (en) * | 2008-11-10 | 2010-05-13 | Pacesetter, Inc. | Enhanced hemodynamics through energy-efficient anodal pacing |
WO2010065465A2 (en) * | 2008-12-02 | 2010-06-10 | Proteus Biomedical, Inc. | Analyzer compatible communication protocol |
US20110082530A1 (en) * | 2009-04-02 | 2011-04-07 | Mark Zdeblick | Method and Apparatus for Implantable Lead |
JP2012525206A (en) * | 2009-04-29 | 2012-10-22 | プロテウス バイオメディカル インコーポレイテッド | Method and apparatus for leads for implantable devices |
US8126546B2 (en) * | 2009-06-30 | 2012-02-28 | Pacesetter, Inc. | Anodal excitation of tissue |
WO2011011736A2 (en) | 2009-07-23 | 2011-01-27 | Proteus Biomedical, Inc. | Solid-state thin film capacitor |
US8934975B2 (en) | 2010-02-01 | 2015-01-13 | Metacure Limited | Gastrointestinal electrical therapy |
US8888699B2 (en) | 2010-04-29 | 2014-11-18 | Medtronic, Inc. | Therapy using perturbation and effect of physiological systems |
US8639327B2 (en) | 2010-04-29 | 2014-01-28 | Medtronic, Inc. | Nerve signal differentiation in cardiac therapy |
US8620425B2 (en) | 2010-04-29 | 2013-12-31 | Medtronic, Inc. | Nerve signal differentiation in cardiac therapy |
US8718770B2 (en) | 2010-10-21 | 2014-05-06 | Medtronic, Inc. | Capture threshold measurement for selection of pacing vector |
WO2012082975A1 (en) * | 2010-12-16 | 2012-06-21 | Med-El Elektromedizinische Geraete Gmbh | Cochlear implant with cochleostomy ground |
US8706223B2 (en) | 2011-01-19 | 2014-04-22 | Medtronic, Inc. | Preventative vagal stimulation |
US8718763B2 (en) | 2011-01-19 | 2014-05-06 | Medtronic, Inc. | Vagal stimulation |
US8781582B2 (en) | 2011-01-19 | 2014-07-15 | Medtronic, Inc. | Vagal stimulation |
US8725259B2 (en) | 2011-01-19 | 2014-05-13 | Medtronic, Inc. | Vagal stimulation |
US8781583B2 (en) | 2011-01-19 | 2014-07-15 | Medtronic, Inc. | Vagal stimulation |
US8355784B2 (en) | 2011-05-13 | 2013-01-15 | Medtronic, Inc. | Dynamic representation of multipolar leads in a programmer interface |
AU2016355338B2 (en) | 2015-11-20 | 2019-04-18 | Cardiac Pacemakers, Inc. | Single pass coronary venous lead for multiple chamber sense and pace |
Family Cites Families (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3937226A (en) * | 1974-07-10 | 1976-02-10 | Medtronic, Inc. | Arrhythmia prevention apparatus |
US4088140A (en) * | 1976-06-18 | 1978-05-09 | Medtronic, Inc. | Demand anti-arrhythmia pacemaker |
US4354497A (en) * | 1977-05-23 | 1982-10-19 | Medtronic, Inc. | Cardiac depolarization detection apparatus |
US4549548A (en) * | 1983-09-14 | 1985-10-29 | Vitafin N.V. | Pacemaker system with automatic event-programmed switching between unipolar and bipolar operation |
US4817605A (en) * | 1984-10-19 | 1989-04-04 | Siemens-Pacesetter, Inc. | Pacemaker system and method for measuring and monitoring cardiac activity and for determining and maintaining capture |
DE3688070T2 (en) * | 1985-12-11 | 1993-06-24 | Telectronics Nv | DEVICE FOR CARDIAC STIMULATION WITH DETECTION OF EVOKED CARDIAC POTENTIALS. |
US5027815A (en) * | 1987-11-25 | 1991-07-02 | Medtronic, Inc. | Dual chamber pacemaker with adaptive atrial escape interval |
US5165403A (en) * | 1991-02-26 | 1992-11-24 | Medtronic, Inc. | Difibrillation lead system and method of use |
US5282837A (en) * | 1991-04-12 | 1994-02-01 | Incontrol, Inc. | Atrial defibrillator and method |
US5273035A (en) * | 1992-02-03 | 1993-12-28 | Medtronic, Inc. | Dual chamber pacemaker with safe airial pacing |
EP0557550B1 (en) * | 1992-02-26 | 1996-12-27 | Pacesetter AB | Rate adaptive cardiac pacemaker |
SE9203284D0 (en) * | 1992-11-04 | 1992-11-04 | Siemens Elema Ab | HJAERTSTIMULATOR |
US5403356A (en) * | 1993-04-28 | 1995-04-04 | Medtronic, Inc. | Method and apparatus for prevention of atrial tachy arrhythmias |
US5314430A (en) * | 1993-06-24 | 1994-05-24 | Medtronic, Inc. | Atrial defibrillator employing transvenous and subcutaneous electrodes and method of use |
US5423772A (en) * | 1993-08-13 | 1995-06-13 | Daig Corporation | Coronary sinus catheter |
FR2718035B1 (en) * | 1994-04-05 | 1996-08-30 | Ela Medical Sa | Method for controlling a double atrial pacemaker of the triple chamber type programmable in fallback mode. |
FR2718036B1 (en) * | 1994-04-05 | 1996-08-30 | Ela Medical Sa | Method for controlling a triple atrial pacemaker of the triple chamber type. |
US5540727A (en) * | 1994-11-15 | 1996-07-30 | Cardiac Pacemakers, Inc. | Method and apparatus to automatically optimize the pacing mode and pacing cycle parameters of a dual chamber pacemaker |
US5607457A (en) * | 1995-09-29 | 1997-03-04 | Schueller; Hans | Pacemaker with evoked response detection by using differential sensing between two unipolar electrodes |
-
1996
- 1996-05-22 US US08/651,741 patent/US5720768A/en not_active Expired - Lifetime
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1997
- 1997-05-15 EP EP97925587A patent/EP0901397A1/en not_active Withdrawn
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- 1997-05-15 JP JP09542548A patent/JP2000511076A/en active Pending
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